Luke's NB Miata Turbo Build
Luke's NB Build – MX5 NutzFeb 2020
Photo: Luke's NB Build – MX5 NutzA Mazda MX-5 NB rebuilt for turbo power and track use
Luke's forum thread follows his NB Miata from track-day daily driver to a full turbo project, starting with bolt-on handling upgrades before a rusty exhaust forced a complete strip-down of the suspension and subframes. The build documents sandblasting, powder coating and rustproofing the underside before turbo parts go on, giving a candid, unfiltered look at doing a driveway rebuild without a garage.
Specs
As stated in the original write-up.
- Roll bar
- GCF roll bar
- Suspension
- Meister R coilovers
- Seats
- Sparco Sprint bucket seats
- Steering wheel
- Sparco steering wheel
- Brake lines
- Hel braided lines
- Brake pads
- Mintex pads
- Radiator
- Tegiwa radiator
- Cooling
- Coolant re-route kit
- Intercooler
- Intercooler and pipework (turbo build)
- Fuel injectors
- RX8 yellow injectors, reconditioned
- ECU
- ME221 standalone ECU
- Planned turbo kit
- G19 manifold and downpipe, TD04 turbo
- Planned clutch
- BOFI clutch
- Bushes
- Polybush full set
Parts used
Parts named as used in the original write-up, grouped the way the Parts page groups them. Where one of the shops we index lists the same thing for this car, it is shown underneath with a link to the shop.
Engine 1
- TD04 turbocharger
Planned turbo unit for the power upgrade
Fuel & Ignition 2
- RX8 fuel injectors
Sourced cheaply from a breaker and cleaned up for the turbo fuelling setup
- G19 turbo manifold and downpipe
Planned as part of the turbo kit
In the shops
Turbo Manifold Kit ↗
MX5 City· $549.11 USD
1.6 Turbo Manifold (New Design) ↗
Flyin' Miata· $549.00 USD
1.8 Turbo Manifold (New Design) ↗Flyin' Miata· $549.00 USD
Cooling 3
- RadiatorTegiwa
New radiator fitted as first step of the turbo build
- Coolant re-route kit
Installed to suit the planned turbo setup
- Intercooler and pipework
Fitted in preparation for turbo installation
Gearbox & Drivetrain 1
- BOFI clutchBOFI
Planned clutch upgrade to handle turbo power
Suspension & Steering 6
- GCF roll barGCF
Fitted early on for track day safety and stiffness
In the shops
Hard Dog Deuce Roll Bar ↗Flyin' Miata· $970.00 USD
Anti-Roll Bar Drop Link ↗
MazSpec MX-5 Spares & Accessories· £12.75 GBP
Rear Anti-Roll Bar Drop Link ↗MazSpec MX-5 Spares & Accessories· £10.50 GBP - Meister R coiloversMeister R
Replaced stock suspension for track-focused handling
- Ball joints
Replaced as part of full suspension rebuild
In the shops
Front Lower Ball Joint ↗MazSpec MX-5 Spares & Accessories· £14.95 GBP
Extended Lower Ball Joints ↗Flyin' Miata· $129.00 USD
Front Lower Ball Joint (QSJ3366S) ↗MazSpec MX-5 Spares & Accessories· £38.75 GBP - Drop links
Replaced as part of full suspension rebuild
In the shopsAnti-Roll Bar Drop Link ↗MazSpec MX-5 Spares & Accessories· £12.75 GBP
ARB Drop Link (Mk3/3.5) ↗MX5 City· $16.88 USD
Drop Link Bush, Polybush ↗Moss Europe (UK)· £11.34 GBP - Rod ends
Replaced as part of full suspension rebuild
In the shops
Right Tie Rod End ↗
Moss Motors – Triumph TR6/TR250· $26.99 USD
Track Rod End Gaiter ↗
TRGB· £3.25 GBP
Left Tie Rod End, S-Type ↗Moss Motors – Triumph TR6/TR250· $24.99 USD - Polybush kit
Fitted throughout the suspension after old bushes were pressed out
Brakes 2
- Hel braided brake linesHel
Fitted for firmer brake feel on track
In the shops
HEL Performance 4-Line Braided Brake Line Kit – Mazda MX-5 NA/NB (MAZ-4-098) ↗MazSpec MX-5 Spares & Accessories· £129.95 GBP
HEL Performance 4-Line Braided Brake Line Kit – Mazda MX-5 NC 1.8/2.0 (MAZ-4-117) ↗MazSpec MX-5 Spares & Accessories· £129.95 GBP
HEL Performance 4-Line Braided Brake Line Kit – Mazda MX-5 ND/RF Brembo (MAZ-4-124) ↗MazSpec MX-5 Spares & Accessories· £129.95 GBP - Mintex brake padsMintex
Fitted alongside braided lines for track use
In the shops
Brake Pad Set, rear, Mintex ↗Moss Europe (UK)· £35.75 GBP
Brake Pad Set, rear, Mintex ↗Moss Europe (UK)· £24.90 GBP
Brake Pad Set, front, Mintex ↗Moss Europe (UK)· £40.80 GBP
Body & Trim 2
- POR15 rust treatmentPOR15
Applied to the front subframe which could not be sandblasted or powder coated
In the shopsFertan Rust Treatment 30ml ↗
MGOC Spares· £4.25Fertan Rust Treatment 500ml ↗MGOC Spares· £20.95Fertan Rust Treatment 1 Litre ↗MGOC Spares· £32.75 - Simoniz underguardSimoniz
Top coat applied over the front subframe after POR15
Interior 2
- Sparco Sprint bucket seatsSparco
Fitted for better track day support
In the shops
Sparco Seat Evo QRT Black ↗
JDMuscle — Mazda MX-5· $929.00 USD
Sparco Base Left Seat Mount ↗JDMuscle — Mazda MX-5· $99.00 USD
Sparco Seat Hardware Spacer Kit - Side Mount ↗JDMuscle — Mazda MX-5· $16.00 USD - Sparco steering wheelSparco
Fitted as part of early interior upgrades
In the shops
Sparco Steering Wheel Hub ↗
Moss Miata· $106.25 USD
SPARCO Steering Wheel Hub ↗JDMuscle — Mazda MX-5· $105.00 USD
Sparco Steering Wheel Hub ↗JDMuscle — Mazda MX-5· $105.00 USD
Electrical 2
- ME221 standalone ECU
Installed to manage the turbo engine
- AEM wideband sensorAEM
Being fitted for air/fuel monitoring; removal of the old O2 sensor exposed exhaust rust
In the shops
AEM X-Series Wideband AFR Sensor and Controller Gauge ↗Moss Miata· $259.99 USD
AEM X-Series Wideband Gauge Kit ↗Flyin' Miata· $259.00 USD
NGK Direct-Fit Wideband Air/Fuel Ratio Sensor (92-00 Civic) ↗JDMuscle — Mazda MX-5· $339.00 USD
Photos
40 pictures collected from the write-up, in the order they were posted, shown from Luke's NB Build – MX5 Nutz. A picture opens larger here, with the way through to the page it is on.
How it was done
Early mods and first track days
Luke bought the NB as a daily driver and track car, fitting a roll bar, coilovers, bucket seats, steering wheel, braided lines and pads. A bad, overcrowded track day at Donington and discovery of chassis rail rust put him off further work, and he briefly considered a Caterham-style kit car instead.
Love rekindled, turbo plans begin
After a much better track day the following year, Luke decided the Miata needed more power to keep up on the straights. He began ordering turbo parts, starting with a new radiator, followed by a coolant re-route kit, intercooler and pipework, reconditioned RX8 injectors and an ME221 ECU.
Rust forces a rethink
While stripping parts to fit a wideband sensor, Luke found the exhaust too rusty to safely remove or replace without risking the car being undriveable. He decided to fully sort the underside and suspension before continuing with any turbo work.
Suspension strip and refurbishment
Luke pulled the rear suspension arms, fighting snapped ABS bolts and seized fasteners, then pressed out old bushes. He ordered new ball joints, drop links, rod ends and a polybush kit, and had the rear uppers sandblasted, powder coated and rebushed.
Front subframe and engine bay clean-up
The front subframe, unable to be sandblasted, was prepped and coated with POR15 followed by Simoniz underguard. The engine bay was cleaned and painted, and various brackets and the engine mounts were sent for powder coating, coming back looking near-mirror finished.
Rebuild and rear subframe work
With the front end refreshed, Luke reassembled the suspension and refit the engine mounts and subframe onto a clean car. He then turned to the rear subframe, encountering a seized PPF bolt that led him to plan removing the whole PPF and differential to free it.
A summary in our own words. The full account, with all its detail, is in the original write-up: read it at Luke's NB Build – MX5 Nutz ↗
Worth knowing
- Check the exhaust and underside condition before starting bolt-on turbo work, or rust can force an unplanned strip-down.
- Seized ABS sensor bolts and long suspension bolts are likely to snap on an older car; budget time for stubborn fasteners.
- Some parts like front subframes may not be suitable for sandblasting, so plan an alternative like POR15 and underguard.
- Label and bag all bolts before a vinegar bath or degreasing so reassembly is not a guessing game.
- Driveway rebuilds without a garage are heavily weather dependent, so timelines will slip.